Threadless interlocking rotary



Oct. 22 19,40. A. E. NIELSEN 21,506

THREADLESS INTERLQCKING ROTARY DRILL PIPE COUPLIflG Original Filed May 18, 1937 1 B Ii M /3 INVENTOR ATTORNEY aeimsaoesn aso UNITED STATES PATENT OFFICE eras 'mnasnmss m'rmocxnm sonar mun. rrrn cournmc Original No. 2,121,710, dated June 21, 1938, Serlal No. 143,370, May 18, 1937.

Application for re- I Ilene May 28, 1939, Serial No. 275,991

5Claims.

This invention relates generally to threadless pipe couplings and is more particularly directed to an improved coupling of this character especially adaptable for joining adJacent lengths or stands of rotary drill pipe such as is employed in the drilling of deep wells, said coupling embodying in its structure certain features similar in character to thoselnherent to the sucker rod coupling disclosed in my copendlng application entitled "Threadless interlocking coupling," flied March 27, 1937, bearing Serial No. 133,458.

It is the principal object of the present invention to provide a threadless drill pipe coupling particularly adaptable for joining drill pipe lengths or stands in a manner to transmit great I torsion, tension and compression strains: which may be easily andquickly assembled and disassembled; which when assembled will provide a f rigid clutch connection preventing relative rol0 tation and endwise movement of the connected members: ,which will take up for wear of the component parts: and which will compensate for radial contraction incident to elongation or stretch of the connecting members.

The invention is exemplified in the following description and illustrated by way of example in the accompanying drawing, in which:

Fig. l is a side elevation. partly in section, illustrating a rotary drill pipe coupling constructed in accordance with the present invention.-

Fig. 2 is a transverse sectional view taken on the line 2-4 of Fig. 1.

I Fig. 3 is a side elevation of the female element of the coupling.

as Fig. (is a side elevation of oi the coupling.

Fig. 5 is an elevation of one of the split sleeve members of the coupling, looking at the interior surface thereof. 1

Fig. 6 is an end view of the female element of the coupling.

Figfllisanendviewofthemaleelement oithe. coupling.

Fig. 8 is an end view illustrating a modified is form of my invention;

Ihe specific-embodiment shown in the drawing isone which is-especially adaptable for use in a. rotarydrill pipe string such as is employed in the drilling of deep oil wells, and which will have 60 a particular utility asa substitute for the standard screw-threaded pin'and box tool Joints commonly employed for connecting the several stands of a drill string.

It is well known that such screw-threaded coniiections do in many instances become-unscrewed the 'male element in deep wells of average depth, requiring upwards of three hours, depending upon the length of the during operations, to cause expensive fishing Jobs, this unscrewing tendency being particularly prevalent in very long drill pipe strings which frequently are subjected to a Wh p g action which at times is very severe, not only in a 5 straight well, which is an exception rather thanthe rule, but to a more pronounced degree in wells of only average straightness which deviate more or less from the verticaL- Another circumstance tending to cause unscrewing of the standard tool joints of the ordinary drill pipe string is occasinned by a sticking of the drill which will cause the long drill pipe to wind up for several turns,

- and its sudden release which will cause the drill and the lower portion of the drill pipe string to rapidly unwind and race ahead of the balance of the string to produce a severe unscrewing tendency.

Rotary drillpipe employed in well drilling is subjected to exceedingly heavy torsional strains, an average size drill pipe of live inch diameter being constructed to withstand a torsional strain of approximately flity tons. Therefore, it is essential that the connections of a drill pipe string be of a. character which will transmit rotary driving strains of this magnitude without relative movement between the parts comprising such connections. Further, since drilling operations cause very severe longitudinal as well as'rotary vibration of the entire drilling string, it is of importance that the several connections be of rigid character so asto eliminate vibratory chatter which would cause crystalimtion and failure of the connecting or coupling members.

It is well known that one ofthe most undesirable features of the standard type of screwthreaded tool Joints is the length of time required to withdraw and disconnect a standard drill string, for such purposes as changing drills or replacing worn cutters. and to make up and run the string into the well again, such round trip,

string.

For these and for other reasons it has long been as considered desirable by those skilled in the art of well drilling to provides rigid fluid-tight rotary drill pipe joint or coupling capable. of supporting the weight oi the drill string without-danger of pulling apart, which cannot become disconnected by rotary influences incident to a drilling operation, and which may be easily and quickly connected or disconnected.

The present'invention provides a rotary drill pipe joint or coupling 0! the desired character as .inadditioniobeingcapableoftransmit- Making up for wearof the connecting elements and of compensating for longitudinal stretch In it; embodiment-disclosed in the drawing, I designates the iemale element while 2 designates the male element of the Joint or coupling, these elements being tubular in character and providing, when brought together, a substantially unobstructed axial flow passage.

The respective end portions 4 and I of the opposed coupling elements I and l are internally -acrew-threaded to receive adjacent drill pipelengths II. However, thedrill pipe may be secured to said portions by welding or by other means.

'l lachoftheseopposedelementsorcoupling members is formed to provide a head A tapered axiallyand inwardly from its outer end and a shank B which is of reduced diameter to provide an intermediate angled abutment shoulder I and is also tapered axially andinwardly from showninl 'lgJr The female element I is counterbored to provide a tapered seat I while'the male element I is provided with ansopposed= conical projection 9 axially disposed and adapted to engage the tapered seat I with a ground lit to form a fluidtight ioint.

To provide additional assurance against iluid leakage. packing grooves ,II are formed in the.

seat portion 8 of the female element and in these grooves are positioned packing rings which engage the conical projection I. when the coupling is assembled.

Surrounding the abutting coupling elements I and 2 are two half sections of a lon8itudinally split coupling sleeve II providing a longitudinal bore having internal walls contoured to closely ,ilttheangularlyre'latedfacesAandBandthe abutment shoulders I of the two adjacent coupling elements, said half sections, when engaged .with the headed coupling members. being slightly separatediromeachothersoastoatalltimes hear directly upon the angularly relatedfaces of bothcouplingmembers.

Thissplit coupling sleeve I lisdisposedbetween an annular portion I oi the female element I and an opposed annular portion I of themale element 1, and for-the purpose of retaining the O is adjacent the groove II to its larger which is adiacent the annular portion I of female elementandisslightly larger'indiamthanissaidannularportiontandforthe of clamping its two half sections tightly heavy rotary drlilingstraim, is also capable" slightly shifted to rest upon the upper end oi the engage over the exterior tapered surface-of the face of the split coupling sleeve Ifand of such diameter that when this outer sleeve I8 is driven longitudinally over the split sleeve I2, it will rigidly clamp the two half sections ofsaid split sleev: upon the opposed coupling elements I g and i v The diameter of the portion I of the male element is less than the diametenof the end portion t to form a'key seat to receive a key II which serves to prevent an endwise releasing movement 10 of the retaining sleeve I. When the key is removed, this'retaining sleeve may be driven on and slid over the portions I and I to release and expose the split sleeve.

In the use of rotary drill pipe inwhlch the standard pin and box tool joints are employed to connect the adjacent stands, it is the usual practice toplace the, tool joints so that the-female or box members thereoi face upwardly so that the companion male or pin members may be more easily and quickly stabbed or inserted therein.

Following this common practice, the joint or coupling herein disclosed will be similarly posi- I outer retaining sleeve l6 having first been slid upwardly over the male coupling member to a position where it will boom of the way until needed. In such position it may, if desired, be

portion 8 of the male member; L

With the opposed coupling elements I and 2 engaged in abutting relationship, the two half sections of the split sleeve II'will he laterally 'applied to embrace the headed coupling members with their internal angular walls closely intermeshing or mating with the angularly related faces A and B and abutment shoulders I of said members, alter which the ring II will be disposed in the groove I! to retain the split sleeve in position until engaged by the outer retaining sleeve. I 1

The outer and clamping sleeve it next be lowered to pass over the-portion i and split sleeve I2 and will then be driven downwardly by suitable means to a tight wedging flt thereon so as to rigidly clamp the two half sections of the inner split sleeve II upon the headed coupling members of the two coupling elements I and '2. Since the maior diameter of the split sleeve is slightly larger than that of the portion 3 of the female element I, this outer sleeve It is free to be driven downwardly until the desired clamping eifect is bad, which will usually be until it can be driven no further by thedriving force applied thereto.

With the outer sleeve thus positioned, the key I! will be'applied as shown in Fig. 1, to prevent 'an upward releasing movementof said outer gs sleeve. I I

If the interlocking'coupling parts become worn through use. such wear may be taken up by-drivingtheoutertaperedsleevefurtheralcngonthe outer-tapered surface of the inner split sleeve, 70 and in the event of longitudinal stretch. of the headed members, such as would cause diametric contraction thereof and a resulting loosening of the wedging en agement of the outer sleeve ll with the inner split sleeve Ifythe weight 15 of said outer sleeve, aided by the vibration of the drill pipe string, will cause an immediate additional downward movement of the outer'sleeve to compensate for such diametric contraction and maintain its clamping function;

While the angularly related faces A and B on the opposed headed coupling members and the similarly angled faces of the inner walls of the split sleeve i! provide a strong and effective clutch means preventing relative rotation of these associated parts, these headed coupling members and the-bore of the split sleeve may be round in cross section and the clutch means may be in the form of matched keys and keyways as suggested in Fig. 8 of the drawing.

Although the present invention is herein disclosed in a preferred form of embodiment, it is to be understood that various changes may be made therein by those skilled in the art without departing from the spirit'of the invention as defined in the appended claims.

Having thus described -my invention, what I claim and desire to secure by Letters Patent is:

1. A coupling comprising maleand female elements each having a bore therethrough and the female element provided with a tapered seat, a

tapered portion formed on said male element to tightly fit the tapered bore of said female elemerit and thereby prevent leakage between said male and female elements, said female element having packing grooves, packing in said grooves and e ing the tapered extension of the male element, groups of angularly related faces formed on the male and female'elements and one group of each element being of a different diameter than the diameter of the other group. a split sleeve having internal faces shaped to match" female elements.

2. A coupling comprising male and female elements each having a bore therethrough and the female element provided with a tapered seat, a taperedportionformedcnsaidmaleeiementto tightly fit the tapered bore of said female element and thereby prevent leakage between said male and female elements. said female element having packing packingdn said grooves and engrooves, .gagingthetapered extension of themale element.

groups of angularly related faces formed on the male and female elements and one group of each elementbeing of adiilerenthiameter than the.

diameteroftheothergrounasplitsieevehaving intsrnalfacesshapedtomatchtheangularlyrelat'ed faces of the male and female elements, and a retaining sleeve embracing the split sleeve and retained against endwise movement thereon.

3. A rotary drill pipe coupling comprising cooperating tubular male and female elements adapted to be axially aligned to provide a continuous fluid passage and formed to provide opposed headed coupling members having angularly tapered portion formed on said male element and adapted to engage said tapered seat and prevent leakage between said malejand female elements.

4. A rotary drill pipe coupling comprising cooperating tubular male and female elements adapted to be axially aligned to provide a continuous fluid passage and formed to provide opposed headed coupling members having angularly related faces, a longitudinally split coupling sleeve adapted to embrace said coupling members and having angularly related internal wall surfaces to match the angularly related faces of said coupling members and a gradually longitudinally tapered exterior surface, an outer clamping sleeve surrounding said split sleeve and having a similarly tapered internal wall surface engaging the tapered external surface of said split sleeve and adapted for axial translation to rigidly clamp said split sleeve on said coupling members, the inner end of said female element being formed to provide a tapered seat, and a tapered portion formed on said male element and adapted to engage said tapered seat and prevent leakage between said male and female elements.

5. A 'rotary drill pipe coupling comprising cooperating tubular male and female elements adapted to be axially aligned to provide a continuous fluid e and formed to provide opposed headed coupling ,members having angularly related clutch faces, a coupling sleeve longitudinally split toprovide opposed sleeve sections each adapted to interlochngly embrace said coupling members and each having angularly related internal wall surfaces to match the clutch faces thereof, contractile means engaging said sleeve sections and tending to yieldingly maintain them in assembled relationship, means operable to rigidly clamp said sleeve sections on said coupling 7 members, the inner end of saidfemale element being formed to provide a tapered seat, and a tapered portion formed on said male element and adapted to engage said tapered seat and prevent leakage between said male'and female elements.

' 'ADOLPH E. NIELSEN. 

